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Development of porous plug phase separator and superfluid film flow suppression system for the Soft X-ray Spectrometer onboard ASTRO-H
Yamaguchi, Hiroya; Ezoe, Yuichiro; Ishikawa, Kumi +10 more
ASTRO-H is the sixth Japanese astronomy satellite scheduled for launch in 2014. The Soft X-ray Spectrometer instrument is onboard ASTRO-H. This is a 6 × 6 array of X-ray microcalorimeters with an energy resolution of <7 eV at 0.5-10 keV. Superfluid liquid helium is utilized as a part of the cooling system. To retain the liquid helium in the tan…
Upper limits on the size of satellites of Asteroid (4) Vesta from 2007 Hubble Space Telescope observations
Mutchler, Max; Hamilton, Douglas P.; Li, Jian-Yang +4 more
We imaged the region around Asteroid (4) Vesta in nine long exposures using the Wide Field Planetary Camera 2 on the Hubble Space Telescope on May 14 and 16, 2007 to conduct a deep search for satellites in support of NASA's Dawn mission that orbited (4) Vesta in 2011-2012. Several previous search efforts have been undertaken, but no satellites wer…
Spectral Evolutions in Gamma-Ray Burst Exponential Decays Observed with Suzaku WAM
Yamaoka, Kazutaka; Onda, Kaori; Sugita, Satoshi +4 more
This paper presents a study on the spectral evolution of gamma-ray burst (GRB) prompt emissions observed with the Suzaku Wide-band All-sky Monitor (WAM). By making use of the WAM data archive, 6 bright GRBs exhibiting 7 well-separated fast-rise-exponential-decay (FRED) shaped light curves are presented, and the evaluated exponential decay time con…
Far-Ultraviolet Spectroscopy of Three Long-Period Novalike Variables
Sion, Edward M.; Godon, Patrick; Bisol, Alexandra C.
We have selected three novalike variables at the long-period extreme of novalike orbital periods: V363 Aur, RZ Gru, and AC Cnc, all with IUE archival far-ultraviolet spectra. All are UX UMa-type novalike variables and all have Porb > 7 hr. V363 Aur is a bona fide SW Sex star, and AC Cnc is a probable one, while RZ Gru has not proven …
Oxygen ion energization by waves in the high altitude cusp and mantle
Waara, M.; Nilsson, H.; Slapak, R. +2 more
We present a comparative study of low frequency electric field spectral densities and temperatures observed by the Cluster spacecraft in the high altitude cusp/mantle region. We compare the relation between the O+ temperature and wave intensity at the oxygen gyrofrequency at each measurement point and find a clear correlation. The trend…
Water ice abundance and CO2 band strength on the saturnian satellite Phoebe from Cassini/VIMS observations
Hansen, Gary B.; Hollenbeck, Emily C.; Stephan, Katrin +2 more
We have studied the near-infrared spectrum of the Saturn satellite Phoebe, a distant satellite observed before Cassini's Saturn orbit insertion, using data from the Visual and Infrared Mapping Spectrometer (VIMS) on the Cassini orbiter. We have done a critical calibration of the dataset that involves careful correction of dark artifacts. We model …
A Weak-lensing and Near-infrared Study of A3192: Disassembling a Richness Class 3 Abell Cluster
Smith, Graham P.; Egami, E.; Marshall, P. J. +5 more
We present a joint gravitational lensing and near-infrared study of the galaxy cluster Abell 3192 (A3192) that has been associated both with galaxies at z = 0.168 and with the X-ray luminous cluster RXC J0358.8-2955 (RXC J0358) at z = 0.425. Weak-lensing analysis of our Hubble Space Telescope snapshot observation with the Advanced Camera for Surve…
Exospheric solar wind charge exchange as seen by XMM-Newton
Read, A. M.; Carter, J. A.; Semba, S.
We review a selection of recent papers describing solar wind charge exchange emission occurring in the Earth's exosphere as seen by the X-ray observatory XMM-Newton. We discuss the detection of this emission, the occurrence with respect to the solar cycle and solar activity, and various spectral signatures observed. We also describe a model develo…
The Pulsational Behavior of the High Amplitude d Scuti Star RS Gruis
García, J.
RS Gruis is a high-amplitude delta Scuti-type variable star with a mean amplitude of almost half a magnitude in V and a period of almost 3.5 hours. The most recent study of this star by Derekas et al. (2009) suggests the presence of a low-mass dwarf star companion close to the variable star with a period of 11.5 days. Rodriguez et al. (1995) have …
Deep optical observations of the massive galaxy cluster Abell 1413
Pointecouteau, E.; Benoist, C.; Maurogordato, S. +4 more
Aims: We investigate the morphology and dynamics of the massive nearby galaxy cluster Abell 1413.
Methods: Using wide field imaging and spectroscopic data obtained from observations at the Canada-France-Hawaii Telescope and archival SDSS data, we build a sample of more than 250 galaxies covering a region centered on the cluster and exten…